package com.jqh.gpuimagelib.render.filter;

import android.content.Context;
import android.opengl.GLES20;

import com.jqh.gpuimagelib.utils.LogUtils;

public class GPUImageWhiteBalanceFilter extends BaseGPUImageFilter {

    public static final String WHITE_BALANCE_FRAGMENT_SHADER = "" +
            "uniform sampler2D inputImageTexture;\n" +
            "varying highp vec2 ft_Position;\n" +
            " \n" +
            "uniform lowp float temperature;\n" +
            "uniform lowp float tint;\n" +
            "\n" +
            "const lowp vec3 warmFilter = vec3(0.93, 0.54, 0.0);\n" +
            "\n" +
            "const mediump mat3 RGBtoYIQ = mat3(0.299, 0.587, 0.114, 0.596, -0.274, -0.322, 0.212, -0.523, 0.311);\n" +
            "const mediump mat3 YIQtoRGB = mat3(1.0, 0.956, 0.621, 1.0, -0.272, -0.647, 1.0, -1.105, 1.702);\n" +
            "\n" +
            "void main()\n" +
            "{\n" +
            "	lowp vec4 source = texture2D(inputImageTexture, ft_Position);\n" +
            "	\n" +
            "	mediump vec3 yiq = RGBtoYIQ * source.rgb; //adjusting tint\n" +
            "	yiq.b = clamp(yiq.b + tint*0.5226*0.1, -0.5226, 0.5226);\n" +
            "	lowp vec3 rgb = YIQtoRGB * yiq;\n" +
            "\n" +
            "	lowp vec3 processed = vec3(\n" +
            "		(rgb.r < 0.5 ? (2.0 * rgb.r * warmFilter.r) : (1.0 - 2.0 * (1.0 - rgb.r) * (1.0 - warmFilter.r))), //adjusting temperature\n" +
            "		(rgb.g < 0.5 ? (2.0 * rgb.g * warmFilter.g) : (1.0 - 2.0 * (1.0 - rgb.g) * (1.0 - warmFilter.g))), \n" +
            "		(rgb.b < 0.5 ? (2.0 * rgb.b * warmFilter.b) : (1.0 - 2.0 * (1.0 - rgb.b) * (1.0 - warmFilter.b))));\n" +
            "\n" +
            "	gl_FragColor = vec4(mix(rgb, processed, temperature), source.a);\n" +
            "}";

    private int temperatureLocation;
    private float temperature;
    private int tintLocation;
    private float tint;

    public GPUImageWhiteBalanceFilter(Context context) {
        this(context, 5000.0f, 0.0f);
    }

    public GPUImageWhiteBalanceFilter(Context context, final float temperature, final float tint) {
        super(context);
        this.temperature = temperature;
        this.tint = tint;
    }


    @Override
    public void init() {
        if (inited) return;
        super.init();
        temperatureLocation = GLES20.glGetUniformLocation(getProgram(), "temperature");
        tintLocation = GLES20.glGetUniformLocation(getProgram(), "tint");
        LogUtils.logd("init whiteblance temperatureLocation = " + temperatureLocation);
    }


    @Override
    public void update() {
        if (!isNeedUpdate) return;
        super.update();
        setFloat(temperatureLocation, temperature);
        setFloat(tintLocation, tint);
    }

    @Override
    public String getFragmentSource() {
        return WHITE_BALANCE_FRAGMENT_SHADER;
    }

}
